I see that bangle.run creates files per session,
When GPS is not working (shows NaN) the created file seems to have content just headers (timestamp,latitude,longitude,altitude,duration,distance,heartrate,steps)
However, when GPS is working it generates a file, corrupt or too big to be downloaded from webIDE, and it happens even if you don't exit the app with BTN3.
Trying to download will produce something like:
*Timed out receiving file
Disconnected from Web Bluetooth, Bangle.js*